With the increasingly stricter requirement for the definition of display apparatuses, the requirement for the effectiveness and instantaneity of the process capability detection is also becoming higher and higher for products with a high recognition rate. For thin-film transistors with a top gate structure employing a low temperature polycrystalline silicon technology, since there are many optical masks during production and the process is complicated, the cost and time for producing the products will be greatly wasted if the defective products cannot be tested instantaneously during the production.
In order to solve the above problems, the process property during the production process of the products is tested with a plurality of test element groups (TEG) separately. In the prior art, each test element group can only test one component in a display apparatus and needs to be provided with a separate test electrode.
In the prior art, there are many test electrodes for a test element group, causing the structure of the test circuit to be complicated, and thus resulting in a low test efficiency and high test cost.